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Conservation of BIODIVERSITY • Biodiversity can be assessed and conserved at several levels: – Molecular/Genetic (rare genes and alleles) – Population – Species – Assemblage – Ecosystem – Global BIODIVERSITY • Molecular/genetic is the level at which natural selection and evolution occurs – Loss of genetic diversity impedes “adaptability” – Loss of populations similarly handicaps a species’ chance of surviving uncertain circumstances in the future. Loss of Biodiversity • Many reasons, often confounded • Historic extinctions – p/t extinction (250 mya) – k/t extinction (65 mya) • Holocene extinctions: 10,000 years ago to present EXTINCTION • “Given evolutionary turnover, extinction is inevitable. Like death for the individual, nothing is more certain in the future of a species than its ultimate removal.” P. Martin and R. G.Klein IN Quarternary Extinctions: A Prehistoric Revolution 1984 Current Extinctions • Current biodiversity crisis – Human mediated • Correlated with Homo sapiens expanding range and density • Ever-quickening rate of extinctions – Has led to increase of 1000 – 10,000% above the rate of background extinctions Current Extinctions • Current biodiversity crisis – Before 1800 • Islands: many unique island assemblages decimated – Gigantic flightless birds – Gigantic tortoises – Dwarf elephants/hippos • Continents: severe extinctions among megafauna – North american mammals – South american marsupials Current Extinctions • After 1800: – Extinctions on islands continue • Birds, endemic mammals, reptiles – Extinctions among smaller continental fauna increase in pace • Habitat destruction/conversion • Unregulated trade • Bounties on “undesirable” species Conservation of Herpetofauna • Amphibians and reptiles face many of the same threats that face other non-human organisms: – – – – – – – – – Habitat modification and destruction Introduction of exotic species Pollution Commercial exploitation Traditional and modern medicine Pets Research and teaching Traffic mortality Persecution Habitat modification and destruction • The most significant problem • Absolutely correlated with increasing human population size • Extensive and worldwide; all biomes, but tropical rainforests hit hardest • “At the current rate of deforestation, within 30 years there will remain neither extensive tropical forests, nor their endemic amphibian and reptile fauna” • from Pough et al. 2001 1) Habitat destruction a) Deforestation of tropical forests b) Destruction of coral reef ecosystems c) Wetland alteration for development d) Temperate regions altered for agriculture e) Habitat fragmentation Habitat modification and destruction • >95% of central California’s marshes were drained and converted before 1900. – Rana aurora draytonii (California red-legged frog), once California’s most common frog, all but disappeared – Thamnophis gigas (giant garter snake), slowly declined, now almost extinct Habitat destruction: Habitat modification and destruction • In Florida, habitat conversion may have been responsible for a decline in Ambystoma cingulatum – 200-300 per night between 1970-1972 – <1 per night after habitat conversion in 19901992 • Anniella pulchra declines correlated with introduced plant spp. Habitat modification and destruction • Often works in tandem with weedy or introduced species – In Arizona, alteration of hydrologic regime enables crayfish, game fish and bullfrogs to persist where they otherwise couldn’t – Argentine ants expanding range into U.S. deserts by utilizing lawns and other landscaping features. Decline in Phrynosoma coronatum and P. cornutum correlated with spread of fire ants Habitat Fragmentation Introduced species • Declines (and extinctions) in many island species attributable to introduced exotics – Dogs and cats: Cyclura carinata in Caicos Islands – Cats: Brachylophus iguanas in the South Pacific – Goats: Crotalus unicolor on Aruba Island – Sheep, goats, rats: Sphenodon in New Zealand – Introduced fish in California’s high elevation lakes: Rana muscosa and Thamnophis spp. – Fire ants impacting Texas horned lizard (P. cornutum) and Coast horned lizard (P. coronutum) – Small Indian Mongoose: 7 species of reptile and amphibian from Puerto Rico Introduced Species: Herps • Bullfrog: western U.S, C. and S. America, England, France, Asia, many other places • Boiga irregularis: Guam – Wiping out geckos and skinks (all birds, bats, many small mammals already gone) • Introduced herp assemblages at ports-ofcall ex ico an a sa s Vi rg in ia Te xa s M ui si K an Id ah o H aw ai i Lo Ne w a a rn i or id ifo Fl Ca l on a ba m a Ar iz Al a Introduced Herps by State (Simberloff et al. 1996) 40 35 30 25 20 15 10 5 0 Pollution – Acid rain: • Ambystoma tigrinum in the Rocky Mountains • Bufo calamita in Britain – Selenium/agriculture runoff: • Thamnophis gigas in California’s Central Valley – Pesticide wafting: Rana and Bufo spp. in the Sierra Nevada Pollution • Solid Waste: marine turtles • PCB’s: effect endocrine systems of aquatic frogs and turtles • Acidic runoff from mines: Rana tarahumarae in Arizona Pollution • Biomagnification – The increase in the concentration of bioaccumulated toxic chemicals in organisms higher on the food chain due to preferential storage of the toxic chemical in edible body parts • There is abundant evidence that some carnivores at the ends of longer food chains (crocodiles, alligators, snakes) suffered serious declines in fecundity and hence in population size because of this phenomenon Anthropogenic eutrophication Directly Impacts aquatic turtle, alligator, snake populations • Nutrients released, triggering chain of events Over-harvesting Commercial collecting: Food • Frogs: U.S., Europe, SE Aisa, Africa – Late 1800’s: extreme decline in availability of California redlegged frogs partially attributable to collecting pressure – 1976- 2.5 million KG frog legs imported into U.S. – Annual consumption in France: 2.7-3.6 million KG frog legs Commercial collecting: Food • Declines in Iguana iguana and Ctenosaura similis • Monitors, pythons, tortoises, sea turtles Commercial collecting: SE Asian Turtle Crisis • 12 million turtles sold per year in China’s food markets • China’s and Vietnam’s turtle populations depleted: now imported from all around the world, including the U.S. • Many of China’s turtles were only known from the food markets: no natural history or distribution information available • Many of those turtles have not been seen in markets for years Commercial collecting: SE Asian Turtle Crisis • Low reproductive rate combined with great importance placed on age of turtle has dire consequences for natural populations The bycatch problem: Commercial exploitation for skins • Civil war: Thousands of American alligators killed for skins • Legal importation of 304,189 pairs of Boa constrictor boots and 176,204 pairs of Python reticulatus into U.S in 1981 (all harvested from the wild) • >1 million crocodile skins per year from 1980 to 1985 • >12 million tegu skins during same period Commercial exploitation for skins • Most species harvested for skins are long-lived • Until recently all have been harvested from the wild • Some progress being made to establish farms for commercially important species • The vast majority of skins are still collected from wild animals Traditional and Modern Medicine • Bufo alvarius and Phyllomedusa bicolor used in shamanistic rituals • Snake venom used in antivenin and anticoagulant drugs • Batrachotoxin used in research to probe for voltage-sensitive sodium channels • Rattlesnake “shaker muscle” used in physiology studies Pets • In Florida, 119,831 herps removed from the wild between 1990-1992 • 74,000 box turtles exported as pets between 1992-1994 • Habitat destruction often accompanies collecting for pets • Very little record kept regarding #’s of animals collected as pets from the wild Pet trade • “In the United States, the retail trade in live reptiles, amphibians, and related products is worth a minimum of two billion dollars annually” -Joseph Franke MS and Teresa Telecky • If you wish a reptile as pet make sure you are dealing with dealer that can be trusted. Find out where the animals come from Research • For scientific collections: usually very small impact • For bio and medical training – In early 1970’s 15 million leopard frogs collected from the wild – 1970-1971: 10 tons of leopard frogs collected from one western state – 250 lbs collected 4 years later Traffic Mortality – Roadkill! Increases mortality of individuals and also decreases gene flow Matthew Aresco, a 4th year PhD student in the Department of Biological Science at Florida State University built a temporary fence to divert turtles (and other wildlife, > 41 species) away from the road and into a culvert that joined the two lakes. Over the past 2.5 years he has monitored the temporary fence at least twice per day and maintained it at his personal expense (at least $2000 out-of-pocket). Species such as frogs, snapping turtles, large softshell turtles, alligators, and most mammals can climb over this low fence. The fence only covers 2000' - 3000' of the "killing zone". Permanent guidewall and culvert system recently constructed at Paynes Prairie on US Highway 441 south of Gainesville, Florida. Persecution http://www.rattlesnakeroundup.com/index.html Rattlesnake Roundups • Occur in several southeastern states • Run by either non-profit Jaycee’s clubs or forprofit companies • 5 Crotalus spp. are targets; other harmless snakes taken incidentally • Collecting methods often unethical • Rattlesnake Roundups Snakes often stockpiled by collectors for long periods of time At roundup, measured, weighed, poked fun at, submitted to stresses and injuries Often skinned alive, in public Rattlesnake Roundups • Justified as a way to “educate the public” • Also, to collect venom for research/antivenin industry • Claims that there’s no effect, or a beneficial effect, on native populations • However, effects of roundups on wild populations largely undocumented Rattlesnake roundups • The only organized events in the U.S. in which profits are made off the unregulated harvest of a vertebrate group • • WHY? Declining Amphibians-History • In 1989, at an international herp conference, workers expressed concern that their study organisms weren’t as common as they once were Declining Amphibians• Species extinctions and population declines around the world prior to 1990 • Subsequent studies have documented declines as they happen • Few patterns emerged, other than that the most precipitous declines were among Anurans Declining Amphibians• Many of the same causes found for other biodiversity losses: – – – – Habitat loss Pollution, acid rain Exotic species Collecting Amphibian Decline: What’s happening to all the frogs? http://www.amphibiaweb.org/aw/declines/extinct.html#declines Evidence of a complex problem Two specimens of deformed frogs (Rana pipiens) from Vermont with missing parts of their hind limbs Deformed Pacific Treefrog, Hyla regilla, from Oregon, with supernumerary hind limbs What’s causing these Deformities/Declines? 1) predation and/or cannibalism? predation and/or cannibalism, whereby some predator (even other tadpoles) may be nipping the limbs off of tadpoles 2) CHEMICAL POLLUTANTS? Retinoic Acid: Main effects of RA on amphibian limbsMethoprene? Atrazine: Diazinon: Suppresses cholinesterase (nervous system) Hayes found hermaphroditism in frogs at levels as low as 0.1 ppb. Even with today's limits, levels of 40 ppb atrazine have been measured in rain and spring water in parts of the Midwest, while atrazine in agricultural runoff can be present at several parts per million. Ribeiroia cercariae 3) Parasites? http://www.jcu.edu.au/school/phtm/ PHTM/frogs/ampdis.htm Ribeiroia ondatrae (trematodes) Johnson et al. exposed tadpole Pacific tree frog (Hyla regilla) to the cercaria of a trematode parasite, Ribeiroia. They found that as the number of parasites per tadpoles rises, the percentage of abnormalities increases while survival decreases. http://news-info.wustl.edu/tips/page/normal/961.html Parasites cont. Spirometra erinacei (tapeworm) Pathogens? Chytrid Fungus (Batrachochytrium dendrobatidis) Mucor amphibiorum Infected frogs and toads have fungi disseminated through their internal organs and skin Infected frogs may: • have discoloured skin • be sloughing, or peeling, on the outside layers of its skin. This can vary from obvious peeling of skin (particularly on the feet), to a roughness of the frog's skin that you can barely see • sit out in the open, not protecting itself by hiding 4) Climate Change? Increase in temperature seems to be impacting amphibian populations 5) Habitat Loss 7) Exotic species • Bullfrog UV Radiation • UVB Radiation? – Blaustein vs Adams and Corn Laws and Regulations: CITES • Convention on International Trade in Endangered Species of Wild Fauna and Flora established by IUCN in 1973 – Regulates international trade in species of concern – Mandates that international trade in endangered species is unlawful – Nearly 600 species of amphibian and reptile are covered Laws and Regulations: ESA • Signed into law by Nixon in 1973 – Far-reaching law; protects both domestic and foreign animals and plants – Prohibits “take” of species of concern – Mandates that FWS and NMFS monitor populations and develop a recovery strategy Laws and Regulations: ESA listing process • Anyone can petition to list a species – Must provide sound scientific basis for listing – FWS or NMFS reviews petition, may conduct additional research, must make findings according to predetermined time schedule – Decision to list or not published in Federal Register, including basis for decision Laws and Regulations: ESA recovery process • FWS or NMFS drafts a Recovery Plan for the species in question – Delineates tasks and criteria needed for the recovery of a species – Solicits public and expert comment on draft Recovery Plan – Revises draft, issues final recovery plan • Includes dollar estimates needed for recovery • Not a binding document – Species is delisted or downlisted as criteria from Recovery Plan are met – Critical habitat may be designated later ESA: Herp Listing Status 100 99 75 49 50 25 1 0 5 Endangered EmE SAT Threatened ESA: Insular and Continental Amphibians and Reptiles 98 100 75 island continental marine 48 50 25 8 0 W es t irg in ia V irg in ia V re go n Te xa s O iss ou ri N ev ad N a ew M ex ico M as hi re go W O Te xa s rn ia ng Wy to om n in g n N ev ad a A la ba m a A riz on a Ca lif o 8 7 6 5 4 3 2 1 0 Id ah o la ba m a A riz on a C al ifo rn ia Fl or id a A ESA Listed Amphibians by State la ba A ma r C izon al ifo a D rni ela a w a G re eo rg i Ill a in oi s Io w M a as M sc ain hu e s M ette in ne s so N ew Mis ta H sou am r N ps i e h N w M ire or th ex C ico ar O olin k Pe lah a o n So nsy ma ut lv a h C nia ar ol in a W as Uta hi h ng to n A M si pp i Te xa s is si s si an a 14 12 10 Lo ui Al ab am a Ca lif or n Fl ia or id a ESA Listed Reptiles by State 8 6 4 2 0 ESA: Herps with Recovery Plans 123 125 100 75 recovery plans listed species 50 31 25 32 13 0 amphibians (42%) reptiles (26%) ESA: Herps with Critical Habitat 134 140 120 100 80 Yes No 60 40 19 20 0 14% w/Critical Habitat ESA: U. S. Listings of Herps by Year 10000 Amphibians Reptiles All species 100 10 2000 1998 1996 1994 1992 1990 1988 1986 1984 1982 1 1980 # Listed 1000 ESA Listed Amphibians and Reptiles by Group 45 41 40 37 35 30 24 25 20 15 19 17 14 10 5 0 2 Anura Urodela Chelonia Crocodylia Rhynchocephalia Sauria Serpentes 100 0. 8 0. 9 16 .8 3. 9 0. 4 100 90 80 70 60 50 40 30 20 10 0 95 .8 % of ESA Listed Species by Group Anura Urodela Chelonia Crocodylia Rhyncocephalia Sauria Serpentes Human Population Density & # ESA Listed Herps 3 Rept. = 0.3426x + 1.3969 R2 = 0.2383 F 1,36 = 11.26, p = 0.002 ln # listed 2.5 2 1.5 Amph.= 0.0453x + 0.5344 R2 = 0.0108 F 1,22 = 0.24, p = 0.63 1 0.5 0 -6 -4 -2 0 ln state population density 2 4 American alligator: an ESA success story • American alligator was listed as threatened under precursuer to ESA in 1967. • All subsequent “take” was illegal • Captive breeding and farming “ranches” proliferated • Eggs collected in wild, incubated, then released when hatched • Alligator recovered, delisted in 1987 • Now subject of 60 million $/ year industry State laws and herps • Usually protected by state game and fish agency • Funding through sales of fishing and hunting licenses (PR act and D-J act, respectively) • Often need fishing or hunting license to collect • Often may not collect for sale • Bag limits, quotas imposed • States may have ESA-type legislation What can I do? • Adopt a conservation ethic • Work directly in the area of conservation – Help conduct research – Assist with conservation organizations – Become involved politically • Educate yourself, family & friends about the importance of herps in the ecosystem • Educate yourself, family & friends about the importance of having better “green” life choices – Try to have a lifestyle that incorporates sustainable methods – Support companies that work towards sustainability & are supportive of the environment – Elect officials that support environmental policies Conservation Groups • • • • • Conservation International The Wildlife Society Society for Conservation Biology The Wilderness Society Center for Biological Diversity Conservation Journals • • • • Conservation Biology Biological Conservation Southwest Naturalist Journal of Wildlife Management, Wildlife Society Bulletin • Chelonian Conservation and Biology When it comes to conservation and all the things of your life keep in mind these words I am only one, but I am one. I cannot do everything, but I can do Something. I will not let what I cannot do interfere with what I can do. Edward Everett Hale